1 /* 2 * segment.c - NILFS segment constructor. 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Ryusuke Konishi <ryusuke@osrg.net> 21 * 22 */ 23 24 #include <linux/pagemap.h> 25 #include <linux/buffer_head.h> 26 #include <linux/writeback.h> 27 #include <linux/bio.h> 28 #include <linux/completion.h> 29 #include <linux/blkdev.h> 30 #include <linux/backing-dev.h> 31 #include <linux/freezer.h> 32 #include <linux/kthread.h> 33 #include <linux/crc32.h> 34 #include <linux/pagevec.h> 35 #include "nilfs.h" 36 #include "btnode.h" 37 #include "page.h" 38 #include "segment.h" 39 #include "sufile.h" 40 #include "cpfile.h" 41 #include "ifile.h" 42 #include "segbuf.h" 43 44 45 /* 46 * Segment constructor 47 */ 48 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ 49 50 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments 51 appended in collection retry loop */ 52 53 /* Construction mode */ 54 enum { 55 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 56 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make 57 a logical segment without a super root */ 58 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without 59 creating a checkpoint */ 60 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without 61 a checkpoint */ 62 }; 63 64 /* Stage numbers of dirty block collection */ 65 enum { 66 NILFS_ST_INIT = 0, 67 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 68 NILFS_ST_FILE, 69 NILFS_ST_IFILE, 70 NILFS_ST_CPFILE, 71 NILFS_ST_SUFILE, 72 NILFS_ST_DAT, 73 NILFS_ST_SR, /* Super root */ 74 NILFS_ST_DSYNC, /* Data sync blocks */ 75 NILFS_ST_DONE, 76 }; 77 78 /* State flags of collection */ 79 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 80 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 81 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 82 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 83 84 /* Operations depending on the construction mode and file type */ 85 struct nilfs_sc_operations { 86 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 87 struct inode *); 88 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 89 struct inode *); 90 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 91 struct inode *); 92 void (*write_data_binfo)(struct nilfs_sc_info *, 93 struct nilfs_segsum_pointer *, 94 union nilfs_binfo *); 95 void (*write_node_binfo)(struct nilfs_sc_info *, 96 struct nilfs_segsum_pointer *, 97 union nilfs_binfo *); 98 }; 99 100 /* 101 * Other definitions 102 */ 103 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 104 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 105 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 106 static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *, 107 int); 108 109 #define nilfs_cnt32_gt(a, b) \ 110 (typecheck(__u32, a) && typecheck(__u32, b) && \ 111 ((__s32)(b) - (__s32)(a) < 0)) 112 #define nilfs_cnt32_ge(a, b) \ 113 (typecheck(__u32, a) && typecheck(__u32, b) && \ 114 ((__s32)(a) - (__s32)(b) >= 0)) 115 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) 116 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) 117 118 /* 119 * Transaction 120 */ 121 static struct kmem_cache *nilfs_transaction_cachep; 122 123 /** 124 * nilfs_init_transaction_cache - create a cache for nilfs_transaction_info 125 * 126 * nilfs_init_transaction_cache() creates a slab cache for the struct 127 * nilfs_transaction_info. 128 * 129 * Return Value: On success, it returns 0. On error, one of the following 130 * negative error code is returned. 131 * 132 * %-ENOMEM - Insufficient memory available. 133 */ 134 int nilfs_init_transaction_cache(void) 135 { 136 nilfs_transaction_cachep = 137 kmem_cache_create("nilfs2_transaction_cache", 138 sizeof(struct nilfs_transaction_info), 139 0, SLAB_RECLAIM_ACCOUNT, NULL); 140 return (nilfs_transaction_cachep == NULL) ? -ENOMEM : 0; 141 } 142 143 /** 144 * nilfs_destroy_transaction_cache - destroy the cache for transaction info 145 * 146 * nilfs_destroy_transaction_cache() frees the slab cache for the struct 147 * nilfs_transaction_info. 148 */ 149 void nilfs_destroy_transaction_cache(void) 150 { 151 kmem_cache_destroy(nilfs_transaction_cachep); 152 } 153 154 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti) 155 { 156 struct nilfs_transaction_info *cur_ti = current->journal_info; 157 void *save = NULL; 158 159 if (cur_ti) { 160 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 161 return ++cur_ti->ti_count; 162 else { 163 /* 164 * If journal_info field is occupied by other FS, 165 * it is saved and will be restored on 166 * nilfs_transaction_commit(). 167 */ 168 printk(KERN_WARNING 169 "NILFS warning: journal info from a different " 170 "FS\n"); 171 save = current->journal_info; 172 } 173 } 174 if (!ti) { 175 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 176 if (!ti) 177 return -ENOMEM; 178 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 179 } else { 180 ti->ti_flags = 0; 181 } 182 ti->ti_count = 0; 183 ti->ti_save = save; 184 ti->ti_magic = NILFS_TI_MAGIC; 185 current->journal_info = ti; 186 return 0; 187 } 188 189 /** 190 * nilfs_transaction_begin - start indivisible file operations. 191 * @sb: super block 192 * @ti: nilfs_transaction_info 193 * @vacancy_check: flags for vacancy rate checks 194 * 195 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 196 * the segment semaphore, to make a segment construction and write tasks 197 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 198 * The region enclosed by these two functions can be nested. To avoid a 199 * deadlock, the semaphore is only acquired or released in the outermost call. 200 * 201 * This function allocates a nilfs_transaction_info struct to keep context 202 * information on it. It is initialized and hooked onto the current task in 203 * the outermost call. If a pre-allocated struct is given to @ti, it is used 204 * instead; othewise a new struct is assigned from a slab. 205 * 206 * When @vacancy_check flag is set, this function will check the amount of 207 * free space, and will wait for the GC to reclaim disk space if low capacity. 208 * 209 * Return Value: On success, 0 is returned. On error, one of the following 210 * negative error code is returned. 211 * 212 * %-ENOMEM - Insufficient memory available. 213 * 214 * %-ENOSPC - No space left on device 215 */ 216 int nilfs_transaction_begin(struct super_block *sb, 217 struct nilfs_transaction_info *ti, 218 int vacancy_check) 219 { 220 struct nilfs_sb_info *sbi; 221 struct the_nilfs *nilfs; 222 int ret = nilfs_prepare_segment_lock(ti); 223 224 if (unlikely(ret < 0)) 225 return ret; 226 if (ret > 0) 227 return 0; 228 229 sbi = NILFS_SB(sb); 230 nilfs = sbi->s_nilfs; 231 down_read(&nilfs->ns_segctor_sem); 232 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 233 up_read(&nilfs->ns_segctor_sem); 234 ret = -ENOSPC; 235 goto failed; 236 } 237 return 0; 238 239 failed: 240 ti = current->journal_info; 241 current->journal_info = ti->ti_save; 242 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 243 kmem_cache_free(nilfs_transaction_cachep, ti); 244 return ret; 245 } 246 247 /** 248 * nilfs_transaction_commit - commit indivisible file operations. 249 * @sb: super block 250 * 251 * nilfs_transaction_commit() releases the read semaphore which is 252 * acquired by nilfs_transaction_begin(). This is only performed 253 * in outermost call of this function. If a commit flag is set, 254 * nilfs_transaction_commit() sets a timer to start the segment 255 * constructor. If a sync flag is set, it starts construction 256 * directly. 257 */ 258 int nilfs_transaction_commit(struct super_block *sb) 259 { 260 struct nilfs_transaction_info *ti = current->journal_info; 261 struct nilfs_sb_info *sbi; 262 struct nilfs_sc_info *sci; 263 int err = 0; 264 265 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 266 ti->ti_flags |= NILFS_TI_COMMIT; 267 if (ti->ti_count > 0) { 268 ti->ti_count--; 269 return 0; 270 } 271 sbi = NILFS_SB(sb); 272 sci = NILFS_SC(sbi); 273 if (sci != NULL) { 274 if (ti->ti_flags & NILFS_TI_COMMIT) 275 nilfs_segctor_start_timer(sci); 276 if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) > 277 sci->sc_watermark) 278 nilfs_segctor_do_flush(sci, 0); 279 } 280 up_read(&sbi->s_nilfs->ns_segctor_sem); 281 current->journal_info = ti->ti_save; 282 283 if (ti->ti_flags & NILFS_TI_SYNC) 284 err = nilfs_construct_segment(sb); 285 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 286 kmem_cache_free(nilfs_transaction_cachep, ti); 287 return err; 288 } 289 290 void nilfs_transaction_abort(struct super_block *sb) 291 { 292 struct nilfs_transaction_info *ti = current->journal_info; 293 294 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 295 if (ti->ti_count > 0) { 296 ti->ti_count--; 297 return; 298 } 299 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem); 300 301 current->journal_info = ti->ti_save; 302 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 303 kmem_cache_free(nilfs_transaction_cachep, ti); 304 } 305 306 void nilfs_relax_pressure_in_lock(struct super_block *sb) 307 { 308 struct nilfs_sb_info *sbi = NILFS_SB(sb); 309 struct nilfs_sc_info *sci = NILFS_SC(sbi); 310 struct the_nilfs *nilfs = sbi->s_nilfs; 311 312 if (!sci || !sci->sc_flush_request) 313 return; 314 315 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 316 up_read(&nilfs->ns_segctor_sem); 317 318 down_write(&nilfs->ns_segctor_sem); 319 if (sci->sc_flush_request && 320 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 321 struct nilfs_transaction_info *ti = current->journal_info; 322 323 ti->ti_flags |= NILFS_TI_WRITER; 324 nilfs_segctor_do_immediate_flush(sci); 325 ti->ti_flags &= ~NILFS_TI_WRITER; 326 } 327 downgrade_write(&nilfs->ns_segctor_sem); 328 } 329 330 static void nilfs_transaction_lock(struct nilfs_sb_info *sbi, 331 struct nilfs_transaction_info *ti, 332 int gcflag) 333 { 334 struct nilfs_transaction_info *cur_ti = current->journal_info; 335 336 WARN_ON(cur_ti); 337 ti->ti_flags = NILFS_TI_WRITER; 338 ti->ti_count = 0; 339 ti->ti_save = cur_ti; 340 ti->ti_magic = NILFS_TI_MAGIC; 341 INIT_LIST_HEAD(&ti->ti_garbage); 342 current->journal_info = ti; 343 344 for (;;) { 345 down_write(&sbi->s_nilfs->ns_segctor_sem); 346 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags)) 347 break; 348 349 nilfs_segctor_do_immediate_flush(NILFS_SC(sbi)); 350 351 up_write(&sbi->s_nilfs->ns_segctor_sem); 352 yield(); 353 } 354 if (gcflag) 355 ti->ti_flags |= NILFS_TI_GC; 356 } 357 358 static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi) 359 { 360 struct nilfs_transaction_info *ti = current->journal_info; 361 362 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 363 BUG_ON(ti->ti_count > 0); 364 365 up_write(&sbi->s_nilfs->ns_segctor_sem); 366 current->journal_info = ti->ti_save; 367 if (!list_empty(&ti->ti_garbage)) 368 nilfs_dispose_list(sbi, &ti->ti_garbage, 0); 369 } 370 371 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 372 struct nilfs_segsum_pointer *ssp, 373 unsigned bytes) 374 { 375 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 376 unsigned blocksize = sci->sc_super->s_blocksize; 377 void *p; 378 379 if (unlikely(ssp->offset + bytes > blocksize)) { 380 ssp->offset = 0; 381 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 382 &segbuf->sb_segsum_buffers)); 383 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 384 } 385 p = ssp->bh->b_data + ssp->offset; 386 ssp->offset += bytes; 387 return p; 388 } 389 390 /** 391 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 392 * @sci: nilfs_sc_info 393 */ 394 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 395 { 396 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 397 struct buffer_head *sumbh; 398 unsigned sumbytes; 399 unsigned flags = 0; 400 int err; 401 402 if (nilfs_doing_gc()) 403 flags = NILFS_SS_GC; 404 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime); 405 if (unlikely(err)) 406 return err; 407 408 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 409 sumbytes = segbuf->sb_sum.sumbytes; 410 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 411 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 412 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 413 return 0; 414 } 415 416 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 417 { 418 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 419 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 420 return -E2BIG; /* The current segment is filled up 421 (internal code) */ 422 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 423 return nilfs_segctor_reset_segment_buffer(sci); 424 } 425 426 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 427 { 428 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 429 int err; 430 431 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 432 err = nilfs_segctor_feed_segment(sci); 433 if (err) 434 return err; 435 segbuf = sci->sc_curseg; 436 } 437 err = nilfs_segbuf_extend_payload(segbuf, &sci->sc_super_root); 438 if (likely(!err)) 439 segbuf->sb_sum.flags |= NILFS_SS_SR; 440 return err; 441 } 442 443 /* 444 * Functions for making segment summary and payloads 445 */ 446 static int nilfs_segctor_segsum_block_required( 447 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 448 unsigned binfo_size) 449 { 450 unsigned blocksize = sci->sc_super->s_blocksize; 451 /* Size of finfo and binfo is enough small against blocksize */ 452 453 return ssp->offset + binfo_size + 454 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 455 blocksize; 456 } 457 458 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 459 struct inode *inode) 460 { 461 sci->sc_curseg->sb_sum.nfinfo++; 462 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 463 nilfs_segctor_map_segsum_entry( 464 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 465 466 if (inode->i_sb && !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 467 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 468 /* skip finfo */ 469 } 470 471 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 472 struct inode *inode) 473 { 474 struct nilfs_finfo *finfo; 475 struct nilfs_inode_info *ii; 476 struct nilfs_segment_buffer *segbuf; 477 478 if (sci->sc_blk_cnt == 0) 479 return; 480 481 ii = NILFS_I(inode); 482 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 483 sizeof(*finfo)); 484 finfo->fi_ino = cpu_to_le64(inode->i_ino); 485 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 486 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 487 finfo->fi_cno = cpu_to_le64(ii->i_cno); 488 489 segbuf = sci->sc_curseg; 490 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 491 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 492 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 493 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 494 } 495 496 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 497 struct buffer_head *bh, 498 struct inode *inode, 499 unsigned binfo_size) 500 { 501 struct nilfs_segment_buffer *segbuf; 502 int required, err = 0; 503 504 retry: 505 segbuf = sci->sc_curseg; 506 required = nilfs_segctor_segsum_block_required( 507 sci, &sci->sc_binfo_ptr, binfo_size); 508 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 509 nilfs_segctor_end_finfo(sci, inode); 510 err = nilfs_segctor_feed_segment(sci); 511 if (err) 512 return err; 513 goto retry; 514 } 515 if (unlikely(required)) { 516 err = nilfs_segbuf_extend_segsum(segbuf); 517 if (unlikely(err)) 518 goto failed; 519 } 520 if (sci->sc_blk_cnt == 0) 521 nilfs_segctor_begin_finfo(sci, inode); 522 523 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 524 /* Substitution to vblocknr is delayed until update_blocknr() */ 525 nilfs_segbuf_add_file_buffer(segbuf, bh); 526 sci->sc_blk_cnt++; 527 failed: 528 return err; 529 } 530 531 static int nilfs_handle_bmap_error(int err, const char *fname, 532 struct inode *inode, struct super_block *sb) 533 { 534 if (err == -EINVAL) { 535 nilfs_error(sb, fname, "broken bmap (inode=%lu)\n", 536 inode->i_ino); 537 err = -EIO; 538 } 539 return err; 540 } 541 542 /* 543 * Callback functions that enumerate, mark, and collect dirty blocks 544 */ 545 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 546 struct buffer_head *bh, struct inode *inode) 547 { 548 int err; 549 550 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 551 if (unlikely(err < 0)) 552 return nilfs_handle_bmap_error(err, __func__, inode, 553 sci->sc_super); 554 555 err = nilfs_segctor_add_file_block(sci, bh, inode, 556 sizeof(struct nilfs_binfo_v)); 557 if (!err) 558 sci->sc_datablk_cnt++; 559 return err; 560 } 561 562 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 563 struct buffer_head *bh, 564 struct inode *inode) 565 { 566 int err; 567 568 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 569 if (unlikely(err < 0)) 570 return nilfs_handle_bmap_error(err, __func__, inode, 571 sci->sc_super); 572 return 0; 573 } 574 575 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 576 struct buffer_head *bh, 577 struct inode *inode) 578 { 579 WARN_ON(!buffer_dirty(bh)); 580 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 581 } 582 583 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 584 struct nilfs_segsum_pointer *ssp, 585 union nilfs_binfo *binfo) 586 { 587 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 588 sci, ssp, sizeof(*binfo_v)); 589 *binfo_v = binfo->bi_v; 590 } 591 592 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 593 struct nilfs_segsum_pointer *ssp, 594 union nilfs_binfo *binfo) 595 { 596 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 597 sci, ssp, sizeof(*vblocknr)); 598 *vblocknr = binfo->bi_v.bi_vblocknr; 599 } 600 601 struct nilfs_sc_operations nilfs_sc_file_ops = { 602 .collect_data = nilfs_collect_file_data, 603 .collect_node = nilfs_collect_file_node, 604 .collect_bmap = nilfs_collect_file_bmap, 605 .write_data_binfo = nilfs_write_file_data_binfo, 606 .write_node_binfo = nilfs_write_file_node_binfo, 607 }; 608 609 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 610 struct buffer_head *bh, struct inode *inode) 611 { 612 int err; 613 614 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 615 if (unlikely(err < 0)) 616 return nilfs_handle_bmap_error(err, __func__, inode, 617 sci->sc_super); 618 619 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 620 if (!err) 621 sci->sc_datablk_cnt++; 622 return err; 623 } 624 625 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 626 struct buffer_head *bh, struct inode *inode) 627 { 628 WARN_ON(!buffer_dirty(bh)); 629 return nilfs_segctor_add_file_block(sci, bh, inode, 630 sizeof(struct nilfs_binfo_dat)); 631 } 632 633 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 634 struct nilfs_segsum_pointer *ssp, 635 union nilfs_binfo *binfo) 636 { 637 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 638 sizeof(*blkoff)); 639 *blkoff = binfo->bi_dat.bi_blkoff; 640 } 641 642 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 643 struct nilfs_segsum_pointer *ssp, 644 union nilfs_binfo *binfo) 645 { 646 struct nilfs_binfo_dat *binfo_dat = 647 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 648 *binfo_dat = binfo->bi_dat; 649 } 650 651 struct nilfs_sc_operations nilfs_sc_dat_ops = { 652 .collect_data = nilfs_collect_dat_data, 653 .collect_node = nilfs_collect_file_node, 654 .collect_bmap = nilfs_collect_dat_bmap, 655 .write_data_binfo = nilfs_write_dat_data_binfo, 656 .write_node_binfo = nilfs_write_dat_node_binfo, 657 }; 658 659 struct nilfs_sc_operations nilfs_sc_dsync_ops = { 660 .collect_data = nilfs_collect_file_data, 661 .collect_node = NULL, 662 .collect_bmap = NULL, 663 .write_data_binfo = nilfs_write_file_data_binfo, 664 .write_node_binfo = NULL, 665 }; 666 667 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 668 struct list_head *listp, 669 size_t nlimit, 670 loff_t start, loff_t end) 671 { 672 struct address_space *mapping = inode->i_mapping; 673 struct pagevec pvec; 674 pgoff_t index = 0, last = ULONG_MAX; 675 size_t ndirties = 0; 676 int i; 677 678 if (unlikely(start != 0 || end != LLONG_MAX)) { 679 /* 680 * A valid range is given for sync-ing data pages. The 681 * range is rounded to per-page; extra dirty buffers 682 * may be included if blocksize < pagesize. 683 */ 684 index = start >> PAGE_SHIFT; 685 last = end >> PAGE_SHIFT; 686 } 687 pagevec_init(&pvec, 0); 688 repeat: 689 if (unlikely(index > last) || 690 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 691 min_t(pgoff_t, last - index, 692 PAGEVEC_SIZE - 1) + 1)) 693 return ndirties; 694 695 for (i = 0; i < pagevec_count(&pvec); i++) { 696 struct buffer_head *bh, *head; 697 struct page *page = pvec.pages[i]; 698 699 if (unlikely(page->index > last)) 700 break; 701 702 if (mapping->host) { 703 lock_page(page); 704 if (!page_has_buffers(page)) 705 create_empty_buffers(page, 706 1 << inode->i_blkbits, 0); 707 unlock_page(page); 708 } 709 710 bh = head = page_buffers(page); 711 do { 712 if (!buffer_dirty(bh)) 713 continue; 714 get_bh(bh); 715 list_add_tail(&bh->b_assoc_buffers, listp); 716 ndirties++; 717 if (unlikely(ndirties >= nlimit)) { 718 pagevec_release(&pvec); 719 cond_resched(); 720 return ndirties; 721 } 722 } while (bh = bh->b_this_page, bh != head); 723 } 724 pagevec_release(&pvec); 725 cond_resched(); 726 goto repeat; 727 } 728 729 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 730 struct list_head *listp) 731 { 732 struct nilfs_inode_info *ii = NILFS_I(inode); 733 struct address_space *mapping = &ii->i_btnode_cache; 734 struct pagevec pvec; 735 struct buffer_head *bh, *head; 736 unsigned int i; 737 pgoff_t index = 0; 738 739 pagevec_init(&pvec, 0); 740 741 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 742 PAGEVEC_SIZE)) { 743 for (i = 0; i < pagevec_count(&pvec); i++) { 744 bh = head = page_buffers(pvec.pages[i]); 745 do { 746 if (buffer_dirty(bh)) { 747 get_bh(bh); 748 list_add_tail(&bh->b_assoc_buffers, 749 listp); 750 } 751 bh = bh->b_this_page; 752 } while (bh != head); 753 } 754 pagevec_release(&pvec); 755 cond_resched(); 756 } 757 } 758 759 static void nilfs_dispose_list(struct nilfs_sb_info *sbi, 760 struct list_head *head, int force) 761 { 762 struct nilfs_inode_info *ii, *n; 763 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 764 unsigned nv = 0; 765 766 while (!list_empty(head)) { 767 spin_lock(&sbi->s_inode_lock); 768 list_for_each_entry_safe(ii, n, head, i_dirty) { 769 list_del_init(&ii->i_dirty); 770 if (force) { 771 if (unlikely(ii->i_bh)) { 772 brelse(ii->i_bh); 773 ii->i_bh = NULL; 774 } 775 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 776 set_bit(NILFS_I_QUEUED, &ii->i_state); 777 list_add_tail(&ii->i_dirty, 778 &sbi->s_dirty_files); 779 continue; 780 } 781 ivec[nv++] = ii; 782 if (nv == SC_N_INODEVEC) 783 break; 784 } 785 spin_unlock(&sbi->s_inode_lock); 786 787 for (pii = ivec; nv > 0; pii++, nv--) 788 iput(&(*pii)->vfs_inode); 789 } 790 } 791 792 static int nilfs_test_metadata_dirty(struct nilfs_sb_info *sbi) 793 { 794 struct the_nilfs *nilfs = sbi->s_nilfs; 795 int ret = 0; 796 797 if (nilfs_mdt_fetch_dirty(sbi->s_ifile)) 798 ret++; 799 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 800 ret++; 801 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 802 ret++; 803 if (ret || nilfs_doing_gc()) 804 if (nilfs_mdt_fetch_dirty(nilfs_dat_inode(nilfs))) 805 ret++; 806 return ret; 807 } 808 809 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 810 { 811 return list_empty(&sci->sc_dirty_files) && 812 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 813 sci->sc_nfreesegs == 0 && 814 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 815 } 816 817 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 818 { 819 struct nilfs_sb_info *sbi = sci->sc_sbi; 820 int ret = 0; 821 822 if (nilfs_test_metadata_dirty(sbi)) 823 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 824 825 spin_lock(&sbi->s_inode_lock); 826 if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci)) 827 ret++; 828 829 spin_unlock(&sbi->s_inode_lock); 830 return ret; 831 } 832 833 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 834 { 835 struct nilfs_sb_info *sbi = sci->sc_sbi; 836 struct the_nilfs *nilfs = sbi->s_nilfs; 837 838 nilfs_mdt_clear_dirty(sbi->s_ifile); 839 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 840 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 841 nilfs_mdt_clear_dirty(nilfs_dat_inode(nilfs)); 842 } 843 844 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 845 { 846 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; 847 struct buffer_head *bh_cp; 848 struct nilfs_checkpoint *raw_cp; 849 int err; 850 851 /* XXX: this interface will be changed */ 852 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 853 &raw_cp, &bh_cp); 854 if (likely(!err)) { 855 /* The following code is duplicated with cpfile. But, it is 856 needed to collect the checkpoint even if it was not newly 857 created */ 858 nilfs_mdt_mark_buffer_dirty(bh_cp); 859 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 860 nilfs_cpfile_put_checkpoint( 861 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 862 } else 863 WARN_ON(err == -EINVAL || err == -ENOENT); 864 865 return err; 866 } 867 868 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 869 { 870 struct nilfs_sb_info *sbi = sci->sc_sbi; 871 struct the_nilfs *nilfs = sbi->s_nilfs; 872 struct buffer_head *bh_cp; 873 struct nilfs_checkpoint *raw_cp; 874 int err; 875 876 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 877 &raw_cp, &bh_cp); 878 if (unlikely(err)) { 879 WARN_ON(err == -EINVAL || err == -ENOENT); 880 goto failed_ibh; 881 } 882 raw_cp->cp_snapshot_list.ssl_next = 0; 883 raw_cp->cp_snapshot_list.ssl_prev = 0; 884 raw_cp->cp_inodes_count = 885 cpu_to_le64(atomic_read(&sbi->s_inodes_count)); 886 raw_cp->cp_blocks_count = 887 cpu_to_le64(atomic_read(&sbi->s_blocks_count)); 888 raw_cp->cp_nblk_inc = 889 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 890 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 891 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 892 893 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 894 nilfs_checkpoint_clear_minor(raw_cp); 895 else 896 nilfs_checkpoint_set_minor(raw_cp); 897 898 nilfs_write_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode, 1); 899 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 900 return 0; 901 902 failed_ibh: 903 return err; 904 } 905 906 static void nilfs_fill_in_file_bmap(struct inode *ifile, 907 struct nilfs_inode_info *ii) 908 909 { 910 struct buffer_head *ibh; 911 struct nilfs_inode *raw_inode; 912 913 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 914 ibh = ii->i_bh; 915 BUG_ON(!ibh); 916 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 917 ibh); 918 nilfs_bmap_write(ii->i_bmap, raw_inode); 919 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 920 } 921 } 922 923 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci, 924 struct inode *ifile) 925 { 926 struct nilfs_inode_info *ii; 927 928 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 929 nilfs_fill_in_file_bmap(ifile, ii); 930 set_bit(NILFS_I_COLLECTED, &ii->i_state); 931 } 932 } 933 934 /* 935 * CRC calculation routines 936 */ 937 static void nilfs_fill_in_super_root_crc(struct buffer_head *bh_sr, u32 seed) 938 { 939 struct nilfs_super_root *raw_sr = 940 (struct nilfs_super_root *)bh_sr->b_data; 941 u32 crc; 942 943 crc = crc32_le(seed, 944 (unsigned char *)raw_sr + sizeof(raw_sr->sr_sum), 945 NILFS_SR_BYTES - sizeof(raw_sr->sr_sum)); 946 raw_sr->sr_sum = cpu_to_le32(crc); 947 } 948 949 static void nilfs_segctor_fill_in_checksums(struct nilfs_sc_info *sci, 950 u32 seed) 951 { 952 struct nilfs_segment_buffer *segbuf; 953 954 if (sci->sc_super_root) 955 nilfs_fill_in_super_root_crc(sci->sc_super_root, seed); 956 957 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 958 nilfs_segbuf_fill_in_segsum_crc(segbuf, seed); 959 nilfs_segbuf_fill_in_data_crc(segbuf, seed); 960 } 961 } 962 963 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 964 struct the_nilfs *nilfs) 965 { 966 struct buffer_head *bh_sr = sci->sc_super_root; 967 struct nilfs_super_root *raw_sr = 968 (struct nilfs_super_root *)bh_sr->b_data; 969 unsigned isz = nilfs->ns_inode_size; 970 971 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES); 972 raw_sr->sr_nongc_ctime 973 = cpu_to_le64(nilfs_doing_gc() ? 974 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 975 raw_sr->sr_flags = 0; 976 977 nilfs_write_inode_common(nilfs_dat_inode(nilfs), (void *)raw_sr + 978 NILFS_SR_DAT_OFFSET(isz), 1); 979 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 980 NILFS_SR_CPFILE_OFFSET(isz), 1); 981 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 982 NILFS_SR_SUFILE_OFFSET(isz), 1); 983 } 984 985 static void nilfs_redirty_inodes(struct list_head *head) 986 { 987 struct nilfs_inode_info *ii; 988 989 list_for_each_entry(ii, head, i_dirty) { 990 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 991 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 992 } 993 } 994 995 static void nilfs_drop_collected_inodes(struct list_head *head) 996 { 997 struct nilfs_inode_info *ii; 998 999 list_for_each_entry(ii, head, i_dirty) { 1000 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 1001 continue; 1002 1003 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state); 1004 set_bit(NILFS_I_UPDATED, &ii->i_state); 1005 } 1006 } 1007 1008 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 1009 struct inode *inode, 1010 struct list_head *listp, 1011 int (*collect)(struct nilfs_sc_info *, 1012 struct buffer_head *, 1013 struct inode *)) 1014 { 1015 struct buffer_head *bh, *n; 1016 int err = 0; 1017 1018 if (collect) { 1019 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1020 list_del_init(&bh->b_assoc_buffers); 1021 err = collect(sci, bh, inode); 1022 brelse(bh); 1023 if (unlikely(err)) 1024 goto dispose_buffers; 1025 } 1026 return 0; 1027 } 1028 1029 dispose_buffers: 1030 while (!list_empty(listp)) { 1031 bh = list_entry(listp->next, struct buffer_head, 1032 b_assoc_buffers); 1033 list_del_init(&bh->b_assoc_buffers); 1034 brelse(bh); 1035 } 1036 return err; 1037 } 1038 1039 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1040 { 1041 /* Remaining number of blocks within segment buffer */ 1042 return sci->sc_segbuf_nblocks - 1043 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1044 } 1045 1046 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1047 struct inode *inode, 1048 struct nilfs_sc_operations *sc_ops) 1049 { 1050 LIST_HEAD(data_buffers); 1051 LIST_HEAD(node_buffers); 1052 int err; 1053 1054 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1055 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1056 1057 n = nilfs_lookup_dirty_data_buffers( 1058 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1059 if (n > rest) { 1060 err = nilfs_segctor_apply_buffers( 1061 sci, inode, &data_buffers, 1062 sc_ops->collect_data); 1063 BUG_ON(!err); /* always receive -E2BIG or true error */ 1064 goto break_or_fail; 1065 } 1066 } 1067 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1068 1069 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1070 err = nilfs_segctor_apply_buffers( 1071 sci, inode, &data_buffers, sc_ops->collect_data); 1072 if (unlikely(err)) { 1073 /* dispose node list */ 1074 nilfs_segctor_apply_buffers( 1075 sci, inode, &node_buffers, NULL); 1076 goto break_or_fail; 1077 } 1078 sci->sc_stage.flags |= NILFS_CF_NODE; 1079 } 1080 /* Collect node */ 1081 err = nilfs_segctor_apply_buffers( 1082 sci, inode, &node_buffers, sc_ops->collect_node); 1083 if (unlikely(err)) 1084 goto break_or_fail; 1085 1086 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1087 err = nilfs_segctor_apply_buffers( 1088 sci, inode, &node_buffers, sc_ops->collect_bmap); 1089 if (unlikely(err)) 1090 goto break_or_fail; 1091 1092 nilfs_segctor_end_finfo(sci, inode); 1093 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1094 1095 break_or_fail: 1096 return err; 1097 } 1098 1099 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1100 struct inode *inode) 1101 { 1102 LIST_HEAD(data_buffers); 1103 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1104 int err; 1105 1106 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1107 sci->sc_dsync_start, 1108 sci->sc_dsync_end); 1109 1110 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1111 nilfs_collect_file_data); 1112 if (!err) { 1113 nilfs_segctor_end_finfo(sci, inode); 1114 BUG_ON(n > rest); 1115 /* always receive -E2BIG or true error if n > rest */ 1116 } 1117 return err; 1118 } 1119 1120 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1121 { 1122 struct nilfs_sb_info *sbi = sci->sc_sbi; 1123 struct the_nilfs *nilfs = sbi->s_nilfs; 1124 struct list_head *head; 1125 struct nilfs_inode_info *ii; 1126 size_t ndone; 1127 int err = 0; 1128 1129 switch (sci->sc_stage.scnt) { 1130 case NILFS_ST_INIT: 1131 /* Pre-processes */ 1132 sci->sc_stage.flags = 0; 1133 1134 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1135 sci->sc_nblk_inc = 0; 1136 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1137 if (mode == SC_LSEG_DSYNC) { 1138 sci->sc_stage.scnt = NILFS_ST_DSYNC; 1139 goto dsync_mode; 1140 } 1141 } 1142 1143 sci->sc_stage.dirty_file_ptr = NULL; 1144 sci->sc_stage.gc_inode_ptr = NULL; 1145 if (mode == SC_FLUSH_DAT) { 1146 sci->sc_stage.scnt = NILFS_ST_DAT; 1147 goto dat_stage; 1148 } 1149 sci->sc_stage.scnt++; /* Fall through */ 1150 case NILFS_ST_GC: 1151 if (nilfs_doing_gc()) { 1152 head = &sci->sc_gc_inodes; 1153 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1154 head, i_dirty); 1155 list_for_each_entry_continue(ii, head, i_dirty) { 1156 err = nilfs_segctor_scan_file( 1157 sci, &ii->vfs_inode, 1158 &nilfs_sc_file_ops); 1159 if (unlikely(err)) { 1160 sci->sc_stage.gc_inode_ptr = list_entry( 1161 ii->i_dirty.prev, 1162 struct nilfs_inode_info, 1163 i_dirty); 1164 goto break_or_fail; 1165 } 1166 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1167 } 1168 sci->sc_stage.gc_inode_ptr = NULL; 1169 } 1170 sci->sc_stage.scnt++; /* Fall through */ 1171 case NILFS_ST_FILE: 1172 head = &sci->sc_dirty_files; 1173 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1174 i_dirty); 1175 list_for_each_entry_continue(ii, head, i_dirty) { 1176 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1177 1178 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1179 &nilfs_sc_file_ops); 1180 if (unlikely(err)) { 1181 sci->sc_stage.dirty_file_ptr = 1182 list_entry(ii->i_dirty.prev, 1183 struct nilfs_inode_info, 1184 i_dirty); 1185 goto break_or_fail; 1186 } 1187 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1188 /* XXX: required ? */ 1189 } 1190 sci->sc_stage.dirty_file_ptr = NULL; 1191 if (mode == SC_FLUSH_FILE) { 1192 sci->sc_stage.scnt = NILFS_ST_DONE; 1193 return 0; 1194 } 1195 sci->sc_stage.scnt++; 1196 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1197 /* Fall through */ 1198 case NILFS_ST_IFILE: 1199 err = nilfs_segctor_scan_file(sci, sbi->s_ifile, 1200 &nilfs_sc_file_ops); 1201 if (unlikely(err)) 1202 break; 1203 sci->sc_stage.scnt++; 1204 /* Creating a checkpoint */ 1205 err = nilfs_segctor_create_checkpoint(sci); 1206 if (unlikely(err)) 1207 break; 1208 /* Fall through */ 1209 case NILFS_ST_CPFILE: 1210 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1211 &nilfs_sc_file_ops); 1212 if (unlikely(err)) 1213 break; 1214 sci->sc_stage.scnt++; /* Fall through */ 1215 case NILFS_ST_SUFILE: 1216 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1217 sci->sc_nfreesegs, &ndone); 1218 if (unlikely(err)) { 1219 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1220 sci->sc_freesegs, ndone, 1221 NULL); 1222 break; 1223 } 1224 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1225 1226 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1227 &nilfs_sc_file_ops); 1228 if (unlikely(err)) 1229 break; 1230 sci->sc_stage.scnt++; /* Fall through */ 1231 case NILFS_ST_DAT: 1232 dat_stage: 1233 err = nilfs_segctor_scan_file(sci, nilfs_dat_inode(nilfs), 1234 &nilfs_sc_dat_ops); 1235 if (unlikely(err)) 1236 break; 1237 if (mode == SC_FLUSH_DAT) { 1238 sci->sc_stage.scnt = NILFS_ST_DONE; 1239 return 0; 1240 } 1241 sci->sc_stage.scnt++; /* Fall through */ 1242 case NILFS_ST_SR: 1243 if (mode == SC_LSEG_SR) { 1244 /* Appending a super root */ 1245 err = nilfs_segctor_add_super_root(sci); 1246 if (unlikely(err)) 1247 break; 1248 } 1249 /* End of a logical segment */ 1250 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1251 sci->sc_stage.scnt = NILFS_ST_DONE; 1252 return 0; 1253 case NILFS_ST_DSYNC: 1254 dsync_mode: 1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1256 ii = sci->sc_dsync_inode; 1257 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1258 break; 1259 1260 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1261 if (unlikely(err)) 1262 break; 1263 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1264 sci->sc_stage.scnt = NILFS_ST_DONE; 1265 return 0; 1266 case NILFS_ST_DONE: 1267 return 0; 1268 default: 1269 BUG(); 1270 } 1271 1272 break_or_fail: 1273 return err; 1274 } 1275 1276 /** 1277 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1278 * @sci: nilfs_sc_info 1279 * @nilfs: nilfs object 1280 */ 1281 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1282 struct the_nilfs *nilfs) 1283 { 1284 struct nilfs_segment_buffer *segbuf, *prev; 1285 __u64 nextnum; 1286 int err, alloc = 0; 1287 1288 segbuf = nilfs_segbuf_new(sci->sc_super); 1289 if (unlikely(!segbuf)) 1290 return -ENOMEM; 1291 1292 if (list_empty(&sci->sc_write_logs)) { 1293 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1294 nilfs->ns_pseg_offset, nilfs); 1295 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1296 nilfs_shift_to_next_segment(nilfs); 1297 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1298 } 1299 1300 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1301 nextnum = nilfs->ns_nextnum; 1302 1303 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1304 /* Start from the head of a new full segment */ 1305 alloc++; 1306 } else { 1307 /* Continue logs */ 1308 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1309 nilfs_segbuf_map_cont(segbuf, prev); 1310 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1311 nextnum = prev->sb_nextnum; 1312 1313 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1314 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1315 segbuf->sb_sum.seg_seq++; 1316 alloc++; 1317 } 1318 } 1319 1320 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1321 if (err) 1322 goto failed; 1323 1324 if (alloc) { 1325 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1326 if (err) 1327 goto failed; 1328 } 1329 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1330 1331 BUG_ON(!list_empty(&sci->sc_segbufs)); 1332 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1333 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1334 return 0; 1335 1336 failed: 1337 nilfs_segbuf_free(segbuf); 1338 return err; 1339 } 1340 1341 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1342 struct the_nilfs *nilfs, int nadd) 1343 { 1344 struct nilfs_segment_buffer *segbuf, *prev; 1345 struct inode *sufile = nilfs->ns_sufile; 1346 __u64 nextnextnum; 1347 LIST_HEAD(list); 1348 int err, ret, i; 1349 1350 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1351 /* 1352 * Since the segment specified with nextnum might be allocated during 1353 * the previous construction, the buffer including its segusage may 1354 * not be dirty. The following call ensures that the buffer is dirty 1355 * and will pin the buffer on memory until the sufile is written. 1356 */ 1357 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1358 if (unlikely(err)) 1359 return err; 1360 1361 for (i = 0; i < nadd; i++) { 1362 /* extend segment info */ 1363 err = -ENOMEM; 1364 segbuf = nilfs_segbuf_new(sci->sc_super); 1365 if (unlikely(!segbuf)) 1366 goto failed; 1367 1368 /* map this buffer to region of segment on-disk */ 1369 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1370 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1371 1372 /* allocate the next next full segment */ 1373 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1374 if (unlikely(err)) 1375 goto failed_segbuf; 1376 1377 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1378 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1379 1380 list_add_tail(&segbuf->sb_list, &list); 1381 prev = segbuf; 1382 } 1383 list_splice_tail(&list, &sci->sc_segbufs); 1384 return 0; 1385 1386 failed_segbuf: 1387 nilfs_segbuf_free(segbuf); 1388 failed: 1389 list_for_each_entry(segbuf, &list, sb_list) { 1390 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1391 WARN_ON(ret); /* never fails */ 1392 } 1393 nilfs_destroy_logs(&list); 1394 return err; 1395 } 1396 1397 static void nilfs_free_incomplete_logs(struct list_head *logs, 1398 struct the_nilfs *nilfs) 1399 { 1400 struct nilfs_segment_buffer *segbuf, *prev; 1401 struct inode *sufile = nilfs->ns_sufile; 1402 int ret; 1403 1404 segbuf = NILFS_FIRST_SEGBUF(logs); 1405 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1406 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1407 WARN_ON(ret); /* never fails */ 1408 } 1409 if (atomic_read(&segbuf->sb_err)) { 1410 /* Case 1: The first segment failed */ 1411 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1412 /* Case 1a: Partial segment appended into an existing 1413 segment */ 1414 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1415 segbuf->sb_fseg_end); 1416 else /* Case 1b: New full segment */ 1417 set_nilfs_discontinued(nilfs); 1418 } 1419 1420 prev = segbuf; 1421 list_for_each_entry_continue(segbuf, logs, sb_list) { 1422 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1423 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1424 WARN_ON(ret); /* never fails */ 1425 } 1426 if (atomic_read(&segbuf->sb_err) && 1427 segbuf->sb_segnum != nilfs->ns_nextnum) 1428 /* Case 2: extended segment (!= next) failed */ 1429 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1430 prev = segbuf; 1431 } 1432 } 1433 1434 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1435 struct inode *sufile) 1436 { 1437 struct nilfs_segment_buffer *segbuf; 1438 unsigned long live_blocks; 1439 int ret; 1440 1441 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1442 live_blocks = segbuf->sb_sum.nblocks + 1443 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1444 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1445 live_blocks, 1446 sci->sc_seg_ctime); 1447 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1448 } 1449 } 1450 1451 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1452 { 1453 struct nilfs_segment_buffer *segbuf; 1454 int ret; 1455 1456 segbuf = NILFS_FIRST_SEGBUF(logs); 1457 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1458 segbuf->sb_pseg_start - 1459 segbuf->sb_fseg_start, 0); 1460 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1461 1462 list_for_each_entry_continue(segbuf, logs, sb_list) { 1463 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1464 0, 0); 1465 WARN_ON(ret); /* always succeed */ 1466 } 1467 } 1468 1469 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1470 struct nilfs_segment_buffer *last, 1471 struct inode *sufile) 1472 { 1473 struct nilfs_segment_buffer *segbuf = last; 1474 int ret; 1475 1476 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1477 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1478 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1479 WARN_ON(ret); 1480 } 1481 nilfs_truncate_logs(&sci->sc_segbufs, last); 1482 } 1483 1484 1485 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1486 struct the_nilfs *nilfs, int mode) 1487 { 1488 struct nilfs_cstage prev_stage = sci->sc_stage; 1489 int err, nadd = 1; 1490 1491 /* Collection retry loop */ 1492 for (;;) { 1493 sci->sc_super_root = NULL; 1494 sci->sc_nblk_this_inc = 0; 1495 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1496 1497 err = nilfs_segctor_reset_segment_buffer(sci); 1498 if (unlikely(err)) 1499 goto failed; 1500 1501 err = nilfs_segctor_collect_blocks(sci, mode); 1502 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1503 if (!err) 1504 break; 1505 1506 if (unlikely(err != -E2BIG)) 1507 goto failed; 1508 1509 /* The current segment is filled up */ 1510 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE) 1511 break; 1512 1513 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1514 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1515 sci->sc_freesegs, 1516 sci->sc_nfreesegs, 1517 NULL); 1518 WARN_ON(err); /* do not happen */ 1519 } 1520 nilfs_clear_logs(&sci->sc_segbufs); 1521 1522 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1523 if (unlikely(err)) 1524 return err; 1525 1526 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1527 sci->sc_stage = prev_stage; 1528 } 1529 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1530 return 0; 1531 1532 failed: 1533 return err; 1534 } 1535 1536 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1537 struct buffer_head *new_bh) 1538 { 1539 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1540 1541 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1542 /* The caller must release old_bh */ 1543 } 1544 1545 static int 1546 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1547 struct nilfs_segment_buffer *segbuf, 1548 int mode) 1549 { 1550 struct inode *inode = NULL; 1551 sector_t blocknr; 1552 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1553 unsigned long nblocks = 0, ndatablk = 0; 1554 struct nilfs_sc_operations *sc_op = NULL; 1555 struct nilfs_segsum_pointer ssp; 1556 struct nilfs_finfo *finfo = NULL; 1557 union nilfs_binfo binfo; 1558 struct buffer_head *bh, *bh_org; 1559 ino_t ino = 0; 1560 int err = 0; 1561 1562 if (!nfinfo) 1563 goto out; 1564 1565 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1566 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1567 ssp.offset = sizeof(struct nilfs_segment_summary); 1568 1569 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1570 if (bh == sci->sc_super_root) 1571 break; 1572 if (!finfo) { 1573 finfo = nilfs_segctor_map_segsum_entry( 1574 sci, &ssp, sizeof(*finfo)); 1575 ino = le64_to_cpu(finfo->fi_ino); 1576 nblocks = le32_to_cpu(finfo->fi_nblocks); 1577 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1578 1579 if (buffer_nilfs_node(bh)) 1580 inode = NILFS_BTNC_I(bh->b_page->mapping); 1581 else 1582 inode = NILFS_AS_I(bh->b_page->mapping); 1583 1584 if (mode == SC_LSEG_DSYNC) 1585 sc_op = &nilfs_sc_dsync_ops; 1586 else if (ino == NILFS_DAT_INO) 1587 sc_op = &nilfs_sc_dat_ops; 1588 else /* file blocks */ 1589 sc_op = &nilfs_sc_file_ops; 1590 } 1591 bh_org = bh; 1592 get_bh(bh_org); 1593 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1594 &binfo); 1595 if (bh != bh_org) 1596 nilfs_list_replace_buffer(bh_org, bh); 1597 brelse(bh_org); 1598 if (unlikely(err)) 1599 goto failed_bmap; 1600 1601 if (ndatablk > 0) 1602 sc_op->write_data_binfo(sci, &ssp, &binfo); 1603 else 1604 sc_op->write_node_binfo(sci, &ssp, &binfo); 1605 1606 blocknr++; 1607 if (--nblocks == 0) { 1608 finfo = NULL; 1609 if (--nfinfo == 0) 1610 break; 1611 } else if (ndatablk > 0) 1612 ndatablk--; 1613 } 1614 out: 1615 return 0; 1616 1617 failed_bmap: 1618 err = nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); 1619 return err; 1620 } 1621 1622 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1623 { 1624 struct nilfs_segment_buffer *segbuf; 1625 int err; 1626 1627 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1628 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1629 if (unlikely(err)) 1630 return err; 1631 nilfs_segbuf_fill_in_segsum(segbuf); 1632 } 1633 return 0; 1634 } 1635 1636 static int 1637 nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out) 1638 { 1639 struct page *clone_page; 1640 struct buffer_head *bh, *head, *bh2; 1641 void *kaddr; 1642 1643 bh = head = page_buffers(page); 1644 1645 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0); 1646 if (unlikely(!clone_page)) 1647 return -ENOMEM; 1648 1649 bh2 = page_buffers(clone_page); 1650 kaddr = kmap_atomic(page, KM_USER0); 1651 do { 1652 if (list_empty(&bh->b_assoc_buffers)) 1653 continue; 1654 get_bh(bh2); 1655 page_cache_get(clone_page); /* for each bh */ 1656 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size); 1657 bh2->b_blocknr = bh->b_blocknr; 1658 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers); 1659 list_add_tail(&bh->b_assoc_buffers, out); 1660 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head); 1661 kunmap_atomic(kaddr, KM_USER0); 1662 1663 if (!TestSetPageWriteback(clone_page)) 1664 inc_zone_page_state(clone_page, NR_WRITEBACK); 1665 unlock_page(clone_page); 1666 1667 return 0; 1668 } 1669 1670 static int nilfs_test_page_to_be_frozen(struct page *page) 1671 { 1672 struct address_space *mapping = page->mapping; 1673 1674 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode)) 1675 return 0; 1676 1677 if (page_mapped(page)) { 1678 ClearPageChecked(page); 1679 return 1; 1680 } 1681 return PageChecked(page); 1682 } 1683 1684 static int nilfs_begin_page_io(struct page *page, struct list_head *out) 1685 { 1686 if (!page || PageWriteback(page)) 1687 /* For split b-tree node pages, this function may be called 1688 twice. We ignore the 2nd or later calls by this check. */ 1689 return 0; 1690 1691 lock_page(page); 1692 clear_page_dirty_for_io(page); 1693 set_page_writeback(page); 1694 unlock_page(page); 1695 1696 if (nilfs_test_page_to_be_frozen(page)) { 1697 int err = nilfs_copy_replace_page_buffers(page, out); 1698 if (unlikely(err)) 1699 return err; 1700 } 1701 return 0; 1702 } 1703 1704 static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci, 1705 struct page **failed_page) 1706 { 1707 struct nilfs_segment_buffer *segbuf; 1708 struct page *bd_page = NULL, *fs_page = NULL; 1709 struct list_head *list = &sci->sc_copied_buffers; 1710 int err; 1711 1712 *failed_page = NULL; 1713 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1714 struct buffer_head *bh; 1715 1716 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1717 b_assoc_buffers) { 1718 if (bh->b_page != bd_page) { 1719 if (bd_page) { 1720 lock_page(bd_page); 1721 clear_page_dirty_for_io(bd_page); 1722 set_page_writeback(bd_page); 1723 unlock_page(bd_page); 1724 } 1725 bd_page = bh->b_page; 1726 } 1727 } 1728 1729 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1730 b_assoc_buffers) { 1731 if (bh == sci->sc_super_root) { 1732 if (bh->b_page != bd_page) { 1733 lock_page(bd_page); 1734 clear_page_dirty_for_io(bd_page); 1735 set_page_writeback(bd_page); 1736 unlock_page(bd_page); 1737 bd_page = bh->b_page; 1738 } 1739 break; 1740 } 1741 if (bh->b_page != fs_page) { 1742 err = nilfs_begin_page_io(fs_page, list); 1743 if (unlikely(err)) { 1744 *failed_page = fs_page; 1745 goto out; 1746 } 1747 fs_page = bh->b_page; 1748 } 1749 } 1750 } 1751 if (bd_page) { 1752 lock_page(bd_page); 1753 clear_page_dirty_for_io(bd_page); 1754 set_page_writeback(bd_page); 1755 unlock_page(bd_page); 1756 } 1757 err = nilfs_begin_page_io(fs_page, list); 1758 if (unlikely(err)) 1759 *failed_page = fs_page; 1760 out: 1761 return err; 1762 } 1763 1764 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1765 struct the_nilfs *nilfs) 1766 { 1767 int ret; 1768 1769 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1770 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1771 return ret; 1772 } 1773 1774 static void __nilfs_end_page_io(struct page *page, int err) 1775 { 1776 if (!err) { 1777 if (!nilfs_page_buffers_clean(page)) 1778 __set_page_dirty_nobuffers(page); 1779 ClearPageError(page); 1780 } else { 1781 __set_page_dirty_nobuffers(page); 1782 SetPageError(page); 1783 } 1784 1785 if (buffer_nilfs_allocated(page_buffers(page))) { 1786 if (TestClearPageWriteback(page)) 1787 dec_zone_page_state(page, NR_WRITEBACK); 1788 } else 1789 end_page_writeback(page); 1790 } 1791 1792 static void nilfs_end_page_io(struct page *page, int err) 1793 { 1794 if (!page) 1795 return; 1796 1797 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1798 /* 1799 * For b-tree node pages, this function may be called twice 1800 * or more because they might be split in a segment. 1801 */ 1802 if (PageDirty(page)) { 1803 /* 1804 * For pages holding split b-tree node buffers, dirty 1805 * flag on the buffers may be cleared discretely. 1806 * In that case, the page is once redirtied for 1807 * remaining buffers, and it must be cancelled if 1808 * all the buffers get cleaned later. 1809 */ 1810 lock_page(page); 1811 if (nilfs_page_buffers_clean(page)) 1812 __nilfs_clear_page_dirty(page); 1813 unlock_page(page); 1814 } 1815 return; 1816 } 1817 1818 __nilfs_end_page_io(page, err); 1819 } 1820 1821 static void nilfs_clear_copied_buffers(struct list_head *list, int err) 1822 { 1823 struct buffer_head *bh, *head; 1824 struct page *page; 1825 1826 while (!list_empty(list)) { 1827 bh = list_entry(list->next, struct buffer_head, 1828 b_assoc_buffers); 1829 page = bh->b_page; 1830 page_cache_get(page); 1831 head = bh = page_buffers(page); 1832 do { 1833 if (!list_empty(&bh->b_assoc_buffers)) { 1834 list_del_init(&bh->b_assoc_buffers); 1835 if (!err) { 1836 set_buffer_uptodate(bh); 1837 clear_buffer_dirty(bh); 1838 clear_buffer_nilfs_volatile(bh); 1839 } 1840 brelse(bh); /* for b_assoc_buffers */ 1841 } 1842 } while ((bh = bh->b_this_page) != head); 1843 1844 __nilfs_end_page_io(page, err); 1845 page_cache_release(page); 1846 } 1847 } 1848 1849 static void nilfs_abort_logs(struct list_head *logs, struct page *failed_page, 1850 struct buffer_head *bh_sr, int err) 1851 { 1852 struct nilfs_segment_buffer *segbuf; 1853 struct page *bd_page = NULL, *fs_page = NULL; 1854 struct buffer_head *bh; 1855 1856 if (list_empty(logs)) 1857 return; 1858 1859 list_for_each_entry(segbuf, logs, sb_list) { 1860 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1861 b_assoc_buffers) { 1862 if (bh->b_page != bd_page) { 1863 if (bd_page) 1864 end_page_writeback(bd_page); 1865 bd_page = bh->b_page; 1866 } 1867 } 1868 1869 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1870 b_assoc_buffers) { 1871 if (bh == bh_sr) { 1872 if (bh->b_page != bd_page) { 1873 end_page_writeback(bd_page); 1874 bd_page = bh->b_page; 1875 } 1876 break; 1877 } 1878 if (bh->b_page != fs_page) { 1879 nilfs_end_page_io(fs_page, err); 1880 if (fs_page && fs_page == failed_page) 1881 return; 1882 fs_page = bh->b_page; 1883 } 1884 } 1885 } 1886 if (bd_page) 1887 end_page_writeback(bd_page); 1888 1889 nilfs_end_page_io(fs_page, err); 1890 } 1891 1892 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1893 struct the_nilfs *nilfs, int err) 1894 { 1895 LIST_HEAD(logs); 1896 int ret; 1897 1898 list_splice_tail_init(&sci->sc_write_logs, &logs); 1899 ret = nilfs_wait_on_logs(&logs); 1900 if (ret) 1901 nilfs_abort_logs(&logs, NULL, sci->sc_super_root, ret); 1902 1903 list_splice_tail_init(&sci->sc_segbufs, &logs); 1904 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1905 nilfs_free_incomplete_logs(&logs, nilfs); 1906 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err); 1907 1908 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1909 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1910 sci->sc_freesegs, 1911 sci->sc_nfreesegs, 1912 NULL); 1913 WARN_ON(ret); /* do not happen */ 1914 } 1915 1916 nilfs_destroy_logs(&logs); 1917 sci->sc_super_root = NULL; 1918 } 1919 1920 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1921 struct nilfs_segment_buffer *segbuf) 1922 { 1923 nilfs->ns_segnum = segbuf->sb_segnum; 1924 nilfs->ns_nextnum = segbuf->sb_nextnum; 1925 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1926 + segbuf->sb_sum.nblocks; 1927 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1928 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1929 } 1930 1931 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1932 { 1933 struct nilfs_segment_buffer *segbuf; 1934 struct page *bd_page = NULL, *fs_page = NULL; 1935 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; 1936 int update_sr = (sci->sc_super_root != NULL); 1937 1938 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1939 struct buffer_head *bh; 1940 1941 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1942 b_assoc_buffers) { 1943 set_buffer_uptodate(bh); 1944 clear_buffer_dirty(bh); 1945 if (bh->b_page != bd_page) { 1946 if (bd_page) 1947 end_page_writeback(bd_page); 1948 bd_page = bh->b_page; 1949 } 1950 } 1951 /* 1952 * We assume that the buffers which belong to the same page 1953 * continue over the buffer list. 1954 * Under this assumption, the last BHs of pages is 1955 * identifiable by the discontinuity of bh->b_page 1956 * (page != fs_page). 1957 * 1958 * For B-tree node blocks, however, this assumption is not 1959 * guaranteed. The cleanup code of B-tree node pages needs 1960 * special care. 1961 */ 1962 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1963 b_assoc_buffers) { 1964 set_buffer_uptodate(bh); 1965 clear_buffer_dirty(bh); 1966 clear_buffer_nilfs_volatile(bh); 1967 if (bh == sci->sc_super_root) { 1968 if (bh->b_page != bd_page) { 1969 end_page_writeback(bd_page); 1970 bd_page = bh->b_page; 1971 } 1972 break; 1973 } 1974 if (bh->b_page != fs_page) { 1975 nilfs_end_page_io(fs_page, 0); 1976 fs_page = bh->b_page; 1977 } 1978 } 1979 1980 if (!NILFS_SEG_SIMPLEX(&segbuf->sb_sum)) { 1981 if (NILFS_SEG_LOGBGN(&segbuf->sb_sum)) { 1982 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1983 sci->sc_lseg_stime = jiffies; 1984 } 1985 if (NILFS_SEG_LOGEND(&segbuf->sb_sum)) 1986 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1987 } 1988 } 1989 /* 1990 * Since pages may continue over multiple segment buffers, 1991 * end of the last page must be checked outside of the loop. 1992 */ 1993 if (bd_page) 1994 end_page_writeback(bd_page); 1995 1996 nilfs_end_page_io(fs_page, 0); 1997 1998 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0); 1999 2000 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 2001 2002 if (nilfs_doing_gc()) { 2003 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 2004 if (update_sr) 2005 nilfs_commit_gcdat_inode(nilfs); 2006 } else 2007 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 2008 2009 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 2010 2011 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 2012 nilfs_set_next_segment(nilfs, segbuf); 2013 2014 if (update_sr) { 2015 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 2016 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 2017 set_nilfs_sb_dirty(nilfs); 2018 2019 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 2020 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2021 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 2022 nilfs_segctor_clear_metadata_dirty(sci); 2023 } else 2024 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 2025 } 2026 2027 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 2028 { 2029 int ret; 2030 2031 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 2032 if (!ret) { 2033 nilfs_segctor_complete_write(sci); 2034 nilfs_destroy_logs(&sci->sc_write_logs); 2035 } 2036 return ret; 2037 } 2038 2039 static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci, 2040 struct nilfs_sb_info *sbi) 2041 { 2042 struct nilfs_inode_info *ii, *n; 2043 __u64 cno = sbi->s_nilfs->ns_cno; 2044 2045 spin_lock(&sbi->s_inode_lock); 2046 retry: 2047 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) { 2048 if (!ii->i_bh) { 2049 struct buffer_head *ibh; 2050 int err; 2051 2052 spin_unlock(&sbi->s_inode_lock); 2053 err = nilfs_ifile_get_inode_block( 2054 sbi->s_ifile, ii->vfs_inode.i_ino, &ibh); 2055 if (unlikely(err)) { 2056 nilfs_warning(sbi->s_super, __func__, 2057 "failed to get inode block.\n"); 2058 return err; 2059 } 2060 nilfs_mdt_mark_buffer_dirty(ibh); 2061 nilfs_mdt_mark_dirty(sbi->s_ifile); 2062 spin_lock(&sbi->s_inode_lock); 2063 if (likely(!ii->i_bh)) 2064 ii->i_bh = ibh; 2065 else 2066 brelse(ibh); 2067 goto retry; 2068 } 2069 ii->i_cno = cno; 2070 2071 clear_bit(NILFS_I_QUEUED, &ii->i_state); 2072 set_bit(NILFS_I_BUSY, &ii->i_state); 2073 list_del(&ii->i_dirty); 2074 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files); 2075 } 2076 spin_unlock(&sbi->s_inode_lock); 2077 2078 NILFS_I(sbi->s_ifile)->i_cno = cno; 2079 2080 return 0; 2081 } 2082 2083 static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci, 2084 struct nilfs_sb_info *sbi) 2085 { 2086 struct nilfs_transaction_info *ti = current->journal_info; 2087 struct nilfs_inode_info *ii, *n; 2088 __u64 cno = sbi->s_nilfs->ns_cno; 2089 2090 spin_lock(&sbi->s_inode_lock); 2091 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 2092 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 2093 test_bit(NILFS_I_DIRTY, &ii->i_state)) { 2094 /* The current checkpoint number (=nilfs->ns_cno) is 2095 changed between check-in and check-out only if the 2096 super root is written out. So, we can update i_cno 2097 for the inodes that remain in the dirty list. */ 2098 ii->i_cno = cno; 2099 continue; 2100 } 2101 clear_bit(NILFS_I_BUSY, &ii->i_state); 2102 brelse(ii->i_bh); 2103 ii->i_bh = NULL; 2104 list_del(&ii->i_dirty); 2105 list_add_tail(&ii->i_dirty, &ti->ti_garbage); 2106 } 2107 spin_unlock(&sbi->s_inode_lock); 2108 } 2109 2110 /* 2111 * Main procedure of segment constructor 2112 */ 2113 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2114 { 2115 struct nilfs_sb_info *sbi = sci->sc_sbi; 2116 struct the_nilfs *nilfs = sbi->s_nilfs; 2117 struct page *failed_page; 2118 int err, has_sr = 0; 2119 2120 sci->sc_stage.scnt = NILFS_ST_INIT; 2121 2122 err = nilfs_segctor_check_in_files(sci, sbi); 2123 if (unlikely(err)) 2124 goto out; 2125 2126 if (nilfs_test_metadata_dirty(sbi)) 2127 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2128 2129 if (nilfs_segctor_clean(sci)) 2130 goto out; 2131 2132 do { 2133 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2134 2135 err = nilfs_segctor_begin_construction(sci, nilfs); 2136 if (unlikely(err)) 2137 goto out; 2138 2139 /* Update time stamp */ 2140 sci->sc_seg_ctime = get_seconds(); 2141 2142 err = nilfs_segctor_collect(sci, nilfs, mode); 2143 if (unlikely(err)) 2144 goto failed; 2145 2146 has_sr = (sci->sc_super_root != NULL); 2147 2148 /* Avoid empty segment */ 2149 if (sci->sc_stage.scnt == NILFS_ST_DONE && 2150 NILFS_SEG_EMPTY(&sci->sc_curseg->sb_sum)) { 2151 nilfs_segctor_abort_construction(sci, nilfs, 1); 2152 goto out; 2153 } 2154 2155 err = nilfs_segctor_assign(sci, mode); 2156 if (unlikely(err)) 2157 goto failed; 2158 2159 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2160 nilfs_segctor_fill_in_file_bmap(sci, sbi->s_ifile); 2161 2162 if (has_sr) { 2163 err = nilfs_segctor_fill_in_checkpoint(sci); 2164 if (unlikely(err)) 2165 goto failed_to_write; 2166 2167 nilfs_segctor_fill_in_super_root(sci, nilfs); 2168 } 2169 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2170 2171 /* Write partial segments */ 2172 err = nilfs_segctor_prepare_write(sci, &failed_page); 2173 if (err) { 2174 nilfs_abort_logs(&sci->sc_segbufs, failed_page, 2175 sci->sc_super_root, err); 2176 goto failed_to_write; 2177 } 2178 nilfs_segctor_fill_in_checksums(sci, nilfs->ns_crc_seed); 2179 2180 err = nilfs_segctor_write(sci, nilfs); 2181 if (unlikely(err)) 2182 goto failed_to_write; 2183 2184 if (sci->sc_stage.scnt == NILFS_ST_DONE || 2185 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) { 2186 /* 2187 * At this point, we avoid double buffering 2188 * for blocksize < pagesize because page dirty 2189 * flag is turned off during write and dirty 2190 * buffers are not properly collected for 2191 * pages crossing over segments. 2192 */ 2193 err = nilfs_segctor_wait(sci); 2194 if (err) 2195 goto failed_to_write; 2196 } 2197 } while (sci->sc_stage.scnt != NILFS_ST_DONE); 2198 2199 sci->sc_super_root = NULL; 2200 2201 out: 2202 nilfs_segctor_check_out_files(sci, sbi); 2203 return err; 2204 2205 failed_to_write: 2206 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2207 nilfs_redirty_inodes(&sci->sc_dirty_files); 2208 2209 failed: 2210 if (nilfs_doing_gc()) 2211 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2212 nilfs_segctor_abort_construction(sci, nilfs, err); 2213 goto out; 2214 } 2215 2216 /** 2217 * nilfs_segctor_start_timer - set timer of background write 2218 * @sci: nilfs_sc_info 2219 * 2220 * If the timer has already been set, it ignores the new request. 2221 * This function MUST be called within a section locking the segment 2222 * semaphore. 2223 */ 2224 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2225 { 2226 spin_lock(&sci->sc_state_lock); 2227 if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2228 sci->sc_timer->expires = jiffies + sci->sc_interval; 2229 add_timer(sci->sc_timer); 2230 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2231 } 2232 spin_unlock(&sci->sc_state_lock); 2233 } 2234 2235 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2236 { 2237 spin_lock(&sci->sc_state_lock); 2238 if (!(sci->sc_flush_request & (1 << bn))) { 2239 unsigned long prev_req = sci->sc_flush_request; 2240 2241 sci->sc_flush_request |= (1 << bn); 2242 if (!prev_req) 2243 wake_up(&sci->sc_wait_daemon); 2244 } 2245 spin_unlock(&sci->sc_state_lock); 2246 } 2247 2248 /** 2249 * nilfs_flush_segment - trigger a segment construction for resource control 2250 * @sb: super block 2251 * @ino: inode number of the file to be flushed out. 2252 */ 2253 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2254 { 2255 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2256 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2257 2258 if (!sci || nilfs_doing_construction()) 2259 return; 2260 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2261 /* assign bit 0 to data files */ 2262 } 2263 2264 struct nilfs_segctor_wait_request { 2265 wait_queue_t wq; 2266 __u32 seq; 2267 int err; 2268 atomic_t done; 2269 }; 2270 2271 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2272 { 2273 struct nilfs_segctor_wait_request wait_req; 2274 int err = 0; 2275 2276 spin_lock(&sci->sc_state_lock); 2277 init_wait(&wait_req.wq); 2278 wait_req.err = 0; 2279 atomic_set(&wait_req.done, 0); 2280 wait_req.seq = ++sci->sc_seq_request; 2281 spin_unlock(&sci->sc_state_lock); 2282 2283 init_waitqueue_entry(&wait_req.wq, current); 2284 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2285 set_current_state(TASK_INTERRUPTIBLE); 2286 wake_up(&sci->sc_wait_daemon); 2287 2288 for (;;) { 2289 if (atomic_read(&wait_req.done)) { 2290 err = wait_req.err; 2291 break; 2292 } 2293 if (!signal_pending(current)) { 2294 schedule(); 2295 continue; 2296 } 2297 err = -ERESTARTSYS; 2298 break; 2299 } 2300 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2301 return err; 2302 } 2303 2304 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2305 { 2306 struct nilfs_segctor_wait_request *wrq, *n; 2307 unsigned long flags; 2308 2309 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2310 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, 2311 wq.task_list) { 2312 if (!atomic_read(&wrq->done) && 2313 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2314 wrq->err = err; 2315 atomic_set(&wrq->done, 1); 2316 } 2317 if (atomic_read(&wrq->done)) { 2318 wrq->wq.func(&wrq->wq, 2319 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2320 0, NULL); 2321 } 2322 } 2323 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2324 } 2325 2326 /** 2327 * nilfs_construct_segment - construct a logical segment 2328 * @sb: super block 2329 * 2330 * Return Value: On success, 0 is retured. On errors, one of the following 2331 * negative error code is returned. 2332 * 2333 * %-EROFS - Read only filesystem. 2334 * 2335 * %-EIO - I/O error 2336 * 2337 * %-ENOSPC - No space left on device (only in a panic state). 2338 * 2339 * %-ERESTARTSYS - Interrupted. 2340 * 2341 * %-ENOMEM - Insufficient memory available. 2342 */ 2343 int nilfs_construct_segment(struct super_block *sb) 2344 { 2345 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2346 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2347 struct nilfs_transaction_info *ti; 2348 int err; 2349 2350 if (!sci) 2351 return -EROFS; 2352 2353 /* A call inside transactions causes a deadlock. */ 2354 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2355 2356 err = nilfs_segctor_sync(sci); 2357 return err; 2358 } 2359 2360 /** 2361 * nilfs_construct_dsync_segment - construct a data-only logical segment 2362 * @sb: super block 2363 * @inode: inode whose data blocks should be written out 2364 * @start: start byte offset 2365 * @end: end byte offset (inclusive) 2366 * 2367 * Return Value: On success, 0 is retured. On errors, one of the following 2368 * negative error code is returned. 2369 * 2370 * %-EROFS - Read only filesystem. 2371 * 2372 * %-EIO - I/O error 2373 * 2374 * %-ENOSPC - No space left on device (only in a panic state). 2375 * 2376 * %-ERESTARTSYS - Interrupted. 2377 * 2378 * %-ENOMEM - Insufficient memory available. 2379 */ 2380 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2381 loff_t start, loff_t end) 2382 { 2383 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2384 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2385 struct nilfs_inode_info *ii; 2386 struct nilfs_transaction_info ti; 2387 int err = 0; 2388 2389 if (!sci) 2390 return -EROFS; 2391 2392 nilfs_transaction_lock(sbi, &ti, 0); 2393 2394 ii = NILFS_I(inode); 2395 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) || 2396 nilfs_test_opt(sbi, STRICT_ORDER) || 2397 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2398 nilfs_discontinued(sbi->s_nilfs)) { 2399 nilfs_transaction_unlock(sbi); 2400 err = nilfs_segctor_sync(sci); 2401 return err; 2402 } 2403 2404 spin_lock(&sbi->s_inode_lock); 2405 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2406 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2407 spin_unlock(&sbi->s_inode_lock); 2408 nilfs_transaction_unlock(sbi); 2409 return 0; 2410 } 2411 spin_unlock(&sbi->s_inode_lock); 2412 sci->sc_dsync_inode = ii; 2413 sci->sc_dsync_start = start; 2414 sci->sc_dsync_end = end; 2415 2416 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2417 2418 nilfs_transaction_unlock(sbi); 2419 return err; 2420 } 2421 2422 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2423 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */ 2424 2425 /** 2426 * nilfs_segctor_accept - record accepted sequence count of log-write requests 2427 * @sci: segment constructor object 2428 */ 2429 static void nilfs_segctor_accept(struct nilfs_sc_info *sci) 2430 { 2431 spin_lock(&sci->sc_state_lock); 2432 sci->sc_seq_accepted = sci->sc_seq_request; 2433 spin_unlock(&sci->sc_state_lock); 2434 2435 if (sci->sc_timer) 2436 del_timer_sync(sci->sc_timer); 2437 } 2438 2439 /** 2440 * nilfs_segctor_notify - notify the result of request to caller threads 2441 * @sci: segment constructor object 2442 * @mode: mode of log forming 2443 * @err: error code to be notified 2444 */ 2445 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 2446 { 2447 /* Clear requests (even when the construction failed) */ 2448 spin_lock(&sci->sc_state_lock); 2449 2450 if (mode == SC_LSEG_SR) { 2451 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2452 sci->sc_seq_done = sci->sc_seq_accepted; 2453 nilfs_segctor_wakeup(sci, err); 2454 sci->sc_flush_request = 0; 2455 } else { 2456 if (mode == SC_FLUSH_FILE) 2457 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2458 else if (mode == SC_FLUSH_DAT) 2459 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2460 2461 /* re-enable timer if checkpoint creation was not done */ 2462 if (sci->sc_timer && (sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2463 time_before(jiffies, sci->sc_timer->expires)) 2464 add_timer(sci->sc_timer); 2465 } 2466 spin_unlock(&sci->sc_state_lock); 2467 } 2468 2469 /** 2470 * nilfs_segctor_construct - form logs and write them to disk 2471 * @sci: segment constructor object 2472 * @mode: mode of log forming 2473 */ 2474 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode) 2475 { 2476 struct nilfs_sb_info *sbi = sci->sc_sbi; 2477 struct the_nilfs *nilfs = sbi->s_nilfs; 2478 int err = 0; 2479 2480 nilfs_segctor_accept(sci); 2481 2482 if (nilfs_discontinued(nilfs)) 2483 mode = SC_LSEG_SR; 2484 if (!nilfs_segctor_confirm(sci)) 2485 err = nilfs_segctor_do_construct(sci, mode); 2486 2487 if (likely(!err)) { 2488 if (mode != SC_FLUSH_DAT) 2489 atomic_set(&nilfs->ns_ndirtyblks, 0); 2490 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2491 nilfs_discontinued(nilfs)) { 2492 down_write(&nilfs->ns_sem); 2493 err = nilfs_commit_super( 2494 sbi, nilfs_altsb_need_update(nilfs)); 2495 up_write(&nilfs->ns_sem); 2496 } 2497 } 2498 2499 nilfs_segctor_notify(sci, mode, err); 2500 return err; 2501 } 2502 2503 static void nilfs_construction_timeout(unsigned long data) 2504 { 2505 struct task_struct *p = (struct task_struct *)data; 2506 wake_up_process(p); 2507 } 2508 2509 static void 2510 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2511 { 2512 struct nilfs_inode_info *ii, *n; 2513 2514 list_for_each_entry_safe(ii, n, head, i_dirty) { 2515 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2516 continue; 2517 hlist_del_init(&ii->vfs_inode.i_hash); 2518 list_del_init(&ii->i_dirty); 2519 nilfs_clear_gcinode(&ii->vfs_inode); 2520 } 2521 } 2522 2523 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2524 void **kbufs) 2525 { 2526 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2527 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2528 struct the_nilfs *nilfs = sbi->s_nilfs; 2529 struct nilfs_transaction_info ti; 2530 int err; 2531 2532 if (unlikely(!sci)) 2533 return -EROFS; 2534 2535 nilfs_transaction_lock(sbi, &ti, 1); 2536 2537 err = nilfs_init_gcdat_inode(nilfs); 2538 if (unlikely(err)) 2539 goto out_unlock; 2540 2541 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2542 if (unlikely(err)) 2543 goto out_unlock; 2544 2545 sci->sc_freesegs = kbufs[4]; 2546 sci->sc_nfreesegs = argv[4].v_nmembs; 2547 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes); 2548 2549 for (;;) { 2550 err = nilfs_segctor_construct(sci, SC_LSEG_SR); 2551 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2552 2553 if (likely(!err)) 2554 break; 2555 2556 nilfs_warning(sb, __func__, 2557 "segment construction failed. (err=%d)", err); 2558 set_current_state(TASK_INTERRUPTIBLE); 2559 schedule_timeout(sci->sc_interval); 2560 } 2561 if (nilfs_test_opt(sbi, DISCARD)) { 2562 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2563 sci->sc_nfreesegs); 2564 if (ret) { 2565 printk(KERN_WARNING 2566 "NILFS warning: error %d on discard request, " 2567 "turning discards off for the device\n", ret); 2568 nilfs_clear_opt(sbi, DISCARD); 2569 } 2570 } 2571 2572 out_unlock: 2573 sci->sc_freesegs = NULL; 2574 sci->sc_nfreesegs = 0; 2575 nilfs_clear_gcdat_inode(nilfs); 2576 nilfs_transaction_unlock(sbi); 2577 return err; 2578 } 2579 2580 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2581 { 2582 struct nilfs_sb_info *sbi = sci->sc_sbi; 2583 struct nilfs_transaction_info ti; 2584 2585 nilfs_transaction_lock(sbi, &ti, 0); 2586 nilfs_segctor_construct(sci, mode); 2587 2588 /* 2589 * Unclosed segment should be retried. We do this using sc_timer. 2590 * Timeout of sc_timer will invoke complete construction which leads 2591 * to close the current logical segment. 2592 */ 2593 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2594 nilfs_segctor_start_timer(sci); 2595 2596 nilfs_transaction_unlock(sbi); 2597 } 2598 2599 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2600 { 2601 int mode = 0; 2602 int err; 2603 2604 spin_lock(&sci->sc_state_lock); 2605 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2606 SC_FLUSH_DAT : SC_FLUSH_FILE; 2607 spin_unlock(&sci->sc_state_lock); 2608 2609 if (mode) { 2610 err = nilfs_segctor_do_construct(sci, mode); 2611 2612 spin_lock(&sci->sc_state_lock); 2613 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2614 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2615 spin_unlock(&sci->sc_state_lock); 2616 } 2617 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2618 } 2619 2620 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2621 { 2622 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2623 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2624 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2625 return SC_FLUSH_FILE; 2626 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2627 return SC_FLUSH_DAT; 2628 } 2629 return SC_LSEG_SR; 2630 } 2631 2632 /** 2633 * nilfs_segctor_thread - main loop of the segment constructor thread. 2634 * @arg: pointer to a struct nilfs_sc_info. 2635 * 2636 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2637 * to execute segment constructions. 2638 */ 2639 static int nilfs_segctor_thread(void *arg) 2640 { 2641 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2642 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; 2643 struct timer_list timer; 2644 int timeout = 0; 2645 2646 init_timer(&timer); 2647 timer.data = (unsigned long)current; 2648 timer.function = nilfs_construction_timeout; 2649 sci->sc_timer = &timer; 2650 2651 /* start sync. */ 2652 sci->sc_task = current; 2653 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2654 printk(KERN_INFO 2655 "segctord starting. Construction interval = %lu seconds, " 2656 "CP frequency < %lu seconds\n", 2657 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2658 2659 spin_lock(&sci->sc_state_lock); 2660 loop: 2661 for (;;) { 2662 int mode; 2663 2664 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2665 goto end_thread; 2666 2667 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2668 mode = SC_LSEG_SR; 2669 else if (!sci->sc_flush_request) 2670 break; 2671 else 2672 mode = nilfs_segctor_flush_mode(sci); 2673 2674 spin_unlock(&sci->sc_state_lock); 2675 nilfs_segctor_thread_construct(sci, mode); 2676 spin_lock(&sci->sc_state_lock); 2677 timeout = 0; 2678 } 2679 2680 2681 if (freezing(current)) { 2682 spin_unlock(&sci->sc_state_lock); 2683 refrigerator(); 2684 spin_lock(&sci->sc_state_lock); 2685 } else { 2686 DEFINE_WAIT(wait); 2687 int should_sleep = 1; 2688 2689 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2690 TASK_INTERRUPTIBLE); 2691 2692 if (sci->sc_seq_request != sci->sc_seq_done) 2693 should_sleep = 0; 2694 else if (sci->sc_flush_request) 2695 should_sleep = 0; 2696 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2697 should_sleep = time_before(jiffies, 2698 sci->sc_timer->expires); 2699 2700 if (should_sleep) { 2701 spin_unlock(&sci->sc_state_lock); 2702 schedule(); 2703 spin_lock(&sci->sc_state_lock); 2704 } 2705 finish_wait(&sci->sc_wait_daemon, &wait); 2706 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2707 time_after_eq(jiffies, sci->sc_timer->expires)); 2708 2709 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2710 set_nilfs_discontinued(nilfs); 2711 } 2712 goto loop; 2713 2714 end_thread: 2715 spin_unlock(&sci->sc_state_lock); 2716 del_timer_sync(sci->sc_timer); 2717 sci->sc_timer = NULL; 2718 2719 /* end sync. */ 2720 sci->sc_task = NULL; 2721 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2722 return 0; 2723 } 2724 2725 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2726 { 2727 struct task_struct *t; 2728 2729 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2730 if (IS_ERR(t)) { 2731 int err = PTR_ERR(t); 2732 2733 printk(KERN_ERR "NILFS: error %d creating segctord thread\n", 2734 err); 2735 return err; 2736 } 2737 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2738 return 0; 2739 } 2740 2741 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2742 { 2743 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2744 2745 while (sci->sc_task) { 2746 wake_up(&sci->sc_wait_daemon); 2747 spin_unlock(&sci->sc_state_lock); 2748 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2749 spin_lock(&sci->sc_state_lock); 2750 } 2751 } 2752 2753 static int nilfs_segctor_init(struct nilfs_sc_info *sci) 2754 { 2755 sci->sc_seq_done = sci->sc_seq_request; 2756 2757 return nilfs_segctor_start_thread(sci); 2758 } 2759 2760 /* 2761 * Setup & clean-up functions 2762 */ 2763 static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi) 2764 { 2765 struct nilfs_sc_info *sci; 2766 2767 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2768 if (!sci) 2769 return NULL; 2770 2771 sci->sc_sbi = sbi; 2772 sci->sc_super = sbi->s_super; 2773 2774 init_waitqueue_head(&sci->sc_wait_request); 2775 init_waitqueue_head(&sci->sc_wait_daemon); 2776 init_waitqueue_head(&sci->sc_wait_task); 2777 spin_lock_init(&sci->sc_state_lock); 2778 INIT_LIST_HEAD(&sci->sc_dirty_files); 2779 INIT_LIST_HEAD(&sci->sc_segbufs); 2780 INIT_LIST_HEAD(&sci->sc_write_logs); 2781 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2782 INIT_LIST_HEAD(&sci->sc_copied_buffers); 2783 2784 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2785 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2786 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2787 2788 if (sbi->s_interval) 2789 sci->sc_interval = sbi->s_interval; 2790 if (sbi->s_watermark) 2791 sci->sc_watermark = sbi->s_watermark; 2792 return sci; 2793 } 2794 2795 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2796 { 2797 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2798 2799 /* The segctord thread was stopped and its timer was removed. 2800 But some tasks remain. */ 2801 do { 2802 struct nilfs_sb_info *sbi = sci->sc_sbi; 2803 struct nilfs_transaction_info ti; 2804 2805 nilfs_transaction_lock(sbi, &ti, 0); 2806 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2807 nilfs_transaction_unlock(sbi); 2808 2809 } while (ret && retrycount-- > 0); 2810 } 2811 2812 /** 2813 * nilfs_segctor_destroy - destroy the segment constructor. 2814 * @sci: nilfs_sc_info 2815 * 2816 * nilfs_segctor_destroy() kills the segctord thread and frees 2817 * the nilfs_sc_info struct. 2818 * Caller must hold the segment semaphore. 2819 */ 2820 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2821 { 2822 struct nilfs_sb_info *sbi = sci->sc_sbi; 2823 int flag; 2824 2825 up_write(&sbi->s_nilfs->ns_segctor_sem); 2826 2827 spin_lock(&sci->sc_state_lock); 2828 nilfs_segctor_kill_thread(sci); 2829 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2830 || sci->sc_seq_request != sci->sc_seq_done); 2831 spin_unlock(&sci->sc_state_lock); 2832 2833 if (flag || !nilfs_segctor_confirm(sci)) 2834 nilfs_segctor_write_out(sci); 2835 2836 WARN_ON(!list_empty(&sci->sc_copied_buffers)); 2837 2838 if (!list_empty(&sci->sc_dirty_files)) { 2839 nilfs_warning(sbi->s_super, __func__, 2840 "dirty file(s) after the final construction\n"); 2841 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1); 2842 } 2843 2844 WARN_ON(!list_empty(&sci->sc_segbufs)); 2845 WARN_ON(!list_empty(&sci->sc_write_logs)); 2846 2847 down_write(&sbi->s_nilfs->ns_segctor_sem); 2848 2849 kfree(sci); 2850 } 2851 2852 /** 2853 * nilfs_attach_segment_constructor - attach a segment constructor 2854 * @sbi: nilfs_sb_info 2855 * 2856 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info, 2857 * initilizes it, and starts the segment constructor. 2858 * 2859 * Return Value: On success, 0 is returned. On error, one of the following 2860 * negative error code is returned. 2861 * 2862 * %-ENOMEM - Insufficient memory available. 2863 */ 2864 int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi) 2865 { 2866 struct the_nilfs *nilfs = sbi->s_nilfs; 2867 int err; 2868 2869 if (NILFS_SC(sbi)) { 2870 /* 2871 * This happens if the filesystem was remounted 2872 * read/write after nilfs_error degenerated it into a 2873 * read-only mount. 2874 */ 2875 nilfs_detach_segment_constructor(sbi); 2876 } 2877 2878 sbi->s_sc_info = nilfs_segctor_new(sbi); 2879 if (!sbi->s_sc_info) 2880 return -ENOMEM; 2881 2882 nilfs_attach_writer(nilfs, sbi); 2883 err = nilfs_segctor_init(NILFS_SC(sbi)); 2884 if (err) { 2885 nilfs_detach_writer(nilfs, sbi); 2886 kfree(sbi->s_sc_info); 2887 sbi->s_sc_info = NULL; 2888 } 2889 return err; 2890 } 2891 2892 /** 2893 * nilfs_detach_segment_constructor - destroy the segment constructor 2894 * @sbi: nilfs_sb_info 2895 * 2896 * nilfs_detach_segment_constructor() kills the segment constructor daemon, 2897 * frees the struct nilfs_sc_info, and destroy the dirty file list. 2898 */ 2899 void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi) 2900 { 2901 struct the_nilfs *nilfs = sbi->s_nilfs; 2902 LIST_HEAD(garbage_list); 2903 2904 down_write(&nilfs->ns_segctor_sem); 2905 if (NILFS_SC(sbi)) { 2906 nilfs_segctor_destroy(NILFS_SC(sbi)); 2907 sbi->s_sc_info = NULL; 2908 } 2909 2910 /* Force to free the list of dirty files */ 2911 spin_lock(&sbi->s_inode_lock); 2912 if (!list_empty(&sbi->s_dirty_files)) { 2913 list_splice_init(&sbi->s_dirty_files, &garbage_list); 2914 nilfs_warning(sbi->s_super, __func__, 2915 "Non empty dirty list after the last " 2916 "segment construction\n"); 2917 } 2918 spin_unlock(&sbi->s_inode_lock); 2919 up_write(&nilfs->ns_segctor_sem); 2920 2921 nilfs_dispose_list(sbi, &garbage_list, 1); 2922 nilfs_detach_writer(nilfs, sbi); 2923 } 2924